Manufacture op highest pressure conduits



Sept. 25,1928. 1,685,402

J. GROSSWEISCHEDE ET AL MANUFACTURE OF HIGHEST PRESSURE CONDUITS Filed Jan. 24, 1927 2 Shets-Sheet 1 /IIIIIIIIIII Sept. 25, 1928.

J. GROSSWEISCHEDE ET AL MANUFACTURE OF HIGHEST PRESSURE GONDUITS Filed Jan. 24. 1927 2 Sheets-Sheet 2 71673! asses during the drawing process in a Patented Sept. 25, 1928.

UNITED STATES PATENT orrice.

JULIUS GROSSWEISCHEDE AND GEORG REICHENBEOHER, OE MULHEIM-RUHR, GER- MANY, ASSIGNORS TO VEREINIGTE STAHLWERKE AKTIENGESELLSCHAFT, OF DUSSELDORF, GERMANY, A GERMAN CORPORATION. I

MANUFACTURE or HIGHEST-PRESSURE CONDUITS.

Application filed January 24; 1927. Serial No. 163,132.

drel and a plurality of dies of gradually de creasing dia1neter'and of increasing length is employed, the work-piece used being a block that is prepared to form a plate, for instance by rolling or forging, and which by this preliminary treatment receives already certain favourable conditions o't its structure which in the succeeding hot-drawing process come very advantageously to effect; a drawn tubular body being then produced with a 4) closed bottom and an open end, both ends being then turther treated as explained hereinatter.

According to the invention, the closed bot tom of the drawn tubular body is cut-out in 5 its middle, so that an inwardly projecting collar is left on the end of the tubular body which is then flanged outwards in any conventional manner, while the open end of the tubular body can be provided with a flange way known in the art by not completely drawing the work-piece during its last pass or passes through the dies.

This kind of the production of. the flanged ends at the conduit allows further, beiore producing the flanges on said ends, to place over the straight tubular body loose flanges, bolted joining-rings, or the like, of smaller diameter than that of the flanges and which are then non-dctachably located between the flanged ends after production of the latter.

The accompanying drawings illustrate how the invention can be put into practice:

Figs. 1 to 5 show, by longitudinal sect-ions, how a. plate is successively termed into a tubular body by the hot-drawing process, Figs. 3, 4t and 5 illustrating besides how the open end of the tubular body is provided with a flange during the drawing process;

9 Fig. 5 is a cross-section on the line VV of Fig. 5;

Fig. 6shows how the closed end of the tubular body is provided with a flange;

Figs. 7 and 8 are longitudinal sections through a finished conduit, respectively made of one tubular body, and of two appropriately joined tubular sections, with loose joining flanges located between its flanged ends;

Fig. '9 illustrates a suitable joining oftwo conduit ends by means of a finely screwthreaded ring screwed over the end flanges of the conduits. V 1

Referring to Figs. 1 to 5: The tubular body a is successively formed of a plate, which is first rolled or forged from a block and thereby made of a dense structure, by the drawing process with the aid of mandrels 1), b 6 Z2 o'l' gradually decreasing diameter and increasing length, and 0t corresponding dies 0, (1 c 0*, c, the inner and outer diameters of the tubular body to be formed being thereby gradually reduced.

As shown in Fig. 5, the collapsible drawmandrel Z), that does not form part of the present invention, consists of a wedge-shaped middle member d tapered toward its front end and on both sides of which the two other members 6 are located and provided with elongated slots 7' in their wedge-shaped surfaces, which are in contact with the middle member (i, into which slots engage projections 9 of said middle member in a slidable way so that the middle member can be displaced and brought out of contact with the two lateral members whereby the diameter or the circumference of the whole mandrel can be reduced and thus the latter can be easily removed from the work-piece drawn.

Figs. 3, i and 5 illustra e also how a flange h can be formed at the open end of the tubular body a during the drawing process by not completely drawing the workpiece through the die, which is preferably done through the last pass or passes of the workpiece.

Fig. 6 shows how the closed end of the tubular body a, after being cut-out in its middle (see dotted lines), is first formed with an inwardly projecting flange, which can then be changed into an outwardly projecting flange i by working said end of the tubular body in any conventional manner.

Fig. 7 shows a finished conduit a with the two end flanges h, i and loose flanges w mounted between the latter so as to fit the tubular body, said conduit being perfectly seamless and thereby adapted to be made of smaller Wall thickness and thus of lighter weight than other conduits used under the same conditions.

Figs. 8 and 9 show how two conduits can be joined, respectively by means of a welded seam or by means of a finely screw-threaded ring is screwed over the end flanges of the conduits, any other appropriate joining being of course possible. 7 l

The inner conduit end of the joint s (Fig. 8) is then obtained from the closed bottom end of the conduit simply by cutting the latter out as far as required, while the outer conduit end of said joint is obtained by outwardly flanging the straight open end of the conduit, whic-hcan also be done by the drawing process.

The cut-out middle pieces of the closed ends of the tubular bodies canbe further used for vany desired practical purpose, for

instance as boiler end plates or the like, so that waste material is completely avoided.

What we claim, is z A method of producing turbine-tubes in preventing the production of germs of cracks, consisting in forming a blank from a thick plate of dense structure by simultaneous .application of pressure and hot drawing with the aid of dies and mandrels of gradually decreasing diameter and of gradually in creasing length a seamless tubular body of gradually decreasing diameter and of gradually increasing length of a special uniform structure, in producing in a manner known per so, during the drawing process an outwardly directed flange at the open end of said tubular body by not drawing the work completely through the die, and in cutting out the bottom of said tubular body to produce an inwardly directed flange.

In testimony whereof we have hereunto set our hands.

JULIUS GROSSWELSCHEDE. GEORG REIGHENBEGHER. 

